Currently, all the browser window titles show the name of the current forum this way in the banner: General forum / UserEcho.
This writing may be not accurate for certain languages.
For instance "Public forum" would be a mistake in French where the normal writing is reversed : "Forum public".
Instead of concatenating the translation of "forum" at the end of the forum name, I suggest to define a full string to be translated, with this kind of content for example:
%(forum_name)s forum -> Forum %(forum_name)s